Does anyone use both display port with 4K monitors?

Hi, Guys:
I am now working on flat screen TV for advertising, so I need a tiny computer which has dual 3840x2160 support in linux.

I think UDOO x86 may be a perfect solution. I do search the internet and this forum, but no one talk about it can support dual 3840x2060 or not.

Any suggestion will be appreciated, thanks.

 

They always said (and the shop is still claiming it) that they can drive multiple 4K screens: "can drive up to three screens in 4K at the same time"

I have it connected to a single HD screen, so I can't tell you if and what problems you'll run into if you want to have multiple 4K screen.

 

Thanks for sharing your DP experience with me.
guess I'll need buy 1 and see if there are another issues or not.

 

btw, note that 4k refresh rate is only 30 Hz - UDOO X86 can't do 60 Hz.

 

that's also important information, thanks!

 

Depending on the OS you are planning to use, there might be some glitches when using two DP ports: https://www.udoo.org/forum/threads/linux-graphic-glitches-when-using-both-display-ports.7280/

 

Thanks, I read the post, and it seems like a xf86-video-intel or linux kernel bug. If I find out which one cause glitches I'll post back here.

 

good news is that UDOO X86 basic support dual 4k@30Hz.
bad news is it can't output single 2k(2560x1440) on 4k monitors.
I just use "xrandr --output DP2 --mode 2560x1440" on 4K monitor, the screen turns black.
Need to use "xrandr --output DP2 --mode 3840x2160" to get my screen back.

My linux distro is Ubuntu 16.04; does anyone know how to solve this issue?

 

Did you install the Linux Graphics Update Tool for ubuntu 16.04?
https://01.org/linuxgraphics/downloads/intel-graphics-update-tool-linux-os-v2.0.2

 

@waltervl : Thanks for reply this information. I haven't try that yet, I'll reply the result ASAP.

 

Thanks @waltervl 's help! now 2560x1440 works great.

I found that Intel Graphics Update Tools is currently V2.0.6(only work in Ubuntu 17.04):
https://01.org/zh/node/10128

I re-install with Ubuntu 17.04 and use this tool, 2K resolution on my 4K monitors finally works now.

 

Sorry for some wrong information, I find out that my working 2K resolutions on DisplayPort is "2048x1080" not "2560x1440";
2560x1440 still get me blank screen on DisplayPort , but it works fine if using HDMI instead.
Windows seems fine on both HDMI & DisplayPort.

Someone had reported this issue: https://bugs.freedesktop.org/show_bug.cgi?id=97031

Let's hope intel-dev will solve this issue soon.

 

Although official fix not ready, for someone urged to use 2560x1440 on DisplayPort may use "xrandr --newmode" for workaround:
gtf 2560 1440 60
# 2560x1440 @ 60.00 Hz (GTF) hsync: 89.40 kHz; pclk: 311.83 MHz
Modeline "2560x1440_60.00" 311.83 2560 2744 3024 3488 1440 1441 1444 1490 -HSync +Vsync

xrandr --newmode "2560x1440_60.00" 311.83 2560 2744 3024 3488 1440 1441 1444 1490 -HSync +Vsync
xrandr --addmode DP2 "2560x1440_60.00"
xradr --output DP2 --mode "2560x1440_60.00"

if previous setting still failed, try "gtf 2560 1440 50" or "gtf 2560 1440 30" for instead, these two settings works for me.